/* "Floating_Nun.java" */
/* <c> 1996 J.H. Rosen */
/* java applet, "Floating_Nun" (nun floats around screen, bouncing off window edges) */

import java.applet.Applet;
import java.awt.*;

public class Floating_Nun extends java.applet.Applet implements Runnable {

 /* constants */

 /* window width X height */
 final int     Window_Width = 500;
 final int     Window_Height = 250;

 /* Floating Nun, width X height */
 final int     Nun_Width = 68;
 final int     Nun_Height = 176;
 
 /* Floating Nun, horiz/vert direction */
 final int     Nun_Move_Up = 0;
 final int     Nun_Move_Down = 1;
 final int     Nun_Move_Left = 0;
 final int     Nun_Move_Right = 1;


 /* variables */

 /* font */
 Font          txt_Font;

 /* Floating Nun image */
 Image         nun_Images[];

 /* Floating Nun, MediaTracker */
 MediaTracker  nun_MediaTracker;

 /* Floating Nun, offscreen graphics context (composite buffer) */
 Image         offNun_Image;
 Graphics      offNun_Graphics;

 /* Floating Nun, horiz/vert coords */
 int           hrz_nun_coord, vrt_nun_coord;
 /* Floating Nun, horiz/vert direction flags */
 int           hrz_nun_direction, vrt_nun_direction;

 /* Floating Nun, frame counter */
 int           nun_FrameCounter;

 /* Floating Nun, animation thread */	
 Thread        animation_Thread;


 /* methods invoked by Java */

 /* "init()"
  * initialize the applet */
 public void init()
 {

  /* loop counter */
  int  lpCnt;

  /* Window_Width X Window_Height canvas */
  resize(Window_Width,Window_Height);
  
  /* text font */
  txt_Font = new Font("Helvetica", Font.PLAIN, 9);

  /* create offscreen graphics context, Floating Nun composite buffer */
  /* rect = 0,0,Window_Width,Window_Height */
  offNun_Image = createImage(Window_Width,Window_Height);
  offNun_Graphics = offNun_Image.getGraphics();

  /* retrieve Floating Nun .gif images */
  /* nun images (4 images) */
  nun_Images = new Image[4];
  for (lpCnt = 0; lpCnt <=3; lpCnt++)
   nun_Images[lpCnt] = getImage(getCodeBase(),("images/nun_" + (lpCnt + 1) + ".gif"));

  /* init Floating Nun MediaTracker */
  nun_MediaTracker = new MediaTracker(this);
  /* load images into MediaTracker */
  for (lpCnt = 0; lpCnt <=3; lpCnt++)
   nun_MediaTracker.addImage(nun_Images[lpCnt],lpCnt);

  /* init (random position within window) Floating Nun, horiz/vert coords */
  hrz_nun_coord = (int) (Math.random() * (Window_Width - Nun_Width));
  vrt_nun_coord = (int) (Math.random() * (Window_Height - Nun_Height));
  /* init Floating Nun, horiz/vert (random up-down/right-left) direction flags */
  hrz_nun_direction = (int) (Math.random() * 2);
  vrt_nun_direction = (int) (Math.random() * 2);

  /* init Floating Nun frame counter */
  nun_FrameCounter = 0;

 } /* end method "init" */


 /* "start()"
  * called when the applet becomes visible on screen */
 public void start()
 {

  /* start scrolling logo animator thread */
  animation_Thread = new Thread(this);
  animation_Thread.start();

 } /* end method "start" */


 /* "run()"
  * called (repeatedly) by the Thread created in "start()" */
 public void run()
 {

  /* update scrolling logo animator thread */
  while (Thread.currentThread() == animation_Thread) {

   /* repaint (update) the screen */
   repaint();

   /* begin: thread delay (125 milliseconds) */
   try {
    Thread.sleep(125);
   } catch (InterruptedException e) {
      break;
     } /* end: thread delay */

  } /* end "while (Thread.currentThread() == animation_Thread)" */

 } /* end method "run" */


 /* "stop()"
  * called when the applet is no longer visible on screen */
 public void stop()
 {

  /* stop scrolling logo animator thread */
  if (animation_Thread != null)
   animation_Thread.stop();

  animation_Thread = null;

 } /* end method "stop" */


 /* "destroy()"
  * called just before the browser exits */
 public void destroy() {

  /* dispose offscreen Graphics Object, Floating Nun composite buffer */
  offNun_Graphics.dispose(); offNun_Graphics = null;

 } /* end method "destroy" */


 /* "update()"
  * update the screen */
 public void update(Graphics  g)
 {

  /* (intercepting "update" avoids background erase) */
  /* call "paint" */
  paint(g);

 } /* end method "update" */


 /* "paint()"
  * paint the screen */
 public void paint(Graphics  g)
 {
  
  /* fill buffer with white paint */
  offNun_Graphics.setColor(Color.white);
  offNun_Graphics.fillRect(0,0,Window_Width,Window_Height);
  /* frame entire buffer with black color */
  offNun_Graphics.setColor(Color.black);
  offNun_Graphics.drawRect(0,0,(Window_Width - 1),(Window_Height - 1));

  /* wait for images to laod before drawing */
  if (nun_MediaTracker.checkAll(true) == true) {

   /* draw nun (in buffer) at specified coords */
   offNun_Graphics.drawImage( nun_Images[nun_FrameCounter],
                              hrz_nun_coord, vrt_nun_coord,this );

   /* change horiz direction (?) */
   if ((hrz_nun_coord + Nun_Width) >= (Window_Width - 1))
    hrz_nun_direction = Nun_Move_Left;
   else if (hrz_nun_coord <= 1)
    hrz_nun_direction = Nun_Move_Right;

   /* change vert direction (?) */
   if ((vrt_nun_coord + Nun_Height) >= (Window_Height - 1))
    vrt_nun_direction = Nun_Move_Up;
   else if (vrt_nun_coord <= 1)
    vrt_nun_direction = Nun_Move_Down;

   /* adjust Floating Nun horiz/vert coords */
   if (hrz_nun_direction == Nun_Move_Right)
    hrz_nun_coord = hrz_nun_coord + 2;
   else
    hrz_nun_coord = hrz_nun_coord - 2;
   if (vrt_nun_direction == Nun_Move_Down)
    vrt_nun_coord = vrt_nun_coord + 2;
   else
    vrt_nun_coord = vrt_nun_coord - 2;

   /* inc/reset Floating Nun frame counter */
   if (nun_FrameCounter < 3)
    nun_FrameCounter++;
   else
    nun_FrameCounter = 0;

  } // end "if (nun_MediaTracker.checkAll(true) == true)"

  /* begin: write text message, "Loading Images..." */
  else {
   /* set text string font */
   offNun_Graphics.setFont(txt_Font);
   /* set text string color */
   offNun_Graphics.setColor(Color.black);
   /* write/draw text message */
   offNun_Graphics.drawString("Loading Images...",25,25);
  }
  /* end: write text message, "Loading Images..." */

  /* blast buffer to screen */
  g.drawImage(offNun_Image,0,0,this);

 } /* end method "paint" */

} /* end class "Floating_Nun" */

/* end file "Floating_Nun.java" */